Method of and apparatus for constrolling the quality or total heating value of alpha lowing mixture of fluids



March 5, 1929. c. s. PINKERTON 1,704,101 I METHOD OF AND APPARATUS FOR CONTROLLING THE QUALITY OR TOTAL HEATING VALUE OF A FLOWING MIXTURE OF FLUIDS Filed April 22, 1926 IIYVENTORI ATTORNEY PHOTO-LUNG by SACKETT 8 WILHELMSCORP N V.

ll' atented ti ler, 5, lll tli CLARENCE s. PINKERTONQQF'MILWAUKEEQIjWKSGQNSIN, assrenoa no run curmu- HAMMER rare. ea, or MILW. AUKELE, 'wrsconsIm-a CORPORATION or Wisconsin.

ian'rn'on or Ann arranarusfnon CONTROLLING THE QUALITY on roman Heartbrevar-arr. or A nnewme MIXTURE or FLUIDS.

Application filed A ni ae, 1926. Serial no. 102,763,

This invention relates to-improvements in methods of and apparatus tor controlling the quality or total heating value" of air-flowing] .inixture of fluids.

More particularly, the invention relates to improvemei'its in methods and apparatus of the character disclosed in the copending application 01 R. H, Kruse, Serial No. 571,018, filed June 26,1922. 1

Anobject ot the invention is .to provide a novel methocLof maintaining a substantially constant total heatmg; ,value of a nnxture 0t substantially constant the total heating value or the mixture.

Another object is to provide such a method wherein a finer adjustment of the relative rates of flow of the combustible fluids may be effected in accordance with the combustion calorific value of the mixture thereof.

Another object is to provide apparatus for enactment of the foregoing methods.

Other objects and-advantages of the inventionwill hereinafter appear.

In most cities, and for many industrial purposes, it is required that gas of substantially constant gross or total heating value be supplied. Ordinarily, the heating value o f the gas is-controlled by mixing two gases which may have widely different qualities, such as natural gas of 1000 B. t. u. per cubic foot and producer gas of 1.50 B. t; u. per cubic foot. Heretofore (as in the Kruse application aforenoted) it has been customary to con- .trol the relative proportions of the gases 1n the mixture in accordance with the determinations of a. suitable calorimeter burning a sample of the mixture. A controller of the type aforementioned is necessarily slow in operation, since there may be a time lag of several minutes before the effect of any change is registered. Such an arrangement is, of course, satisfactory Where the changes occur slowly" or gradually. In many cases, however, the gas flow phanges rapidly, due to -the desired heating value.

the mixture passing throughpipe 5.

changes in the demand for gas, and it is then I essential to make quick changes in the rela tive rates of flow of the two streams of gas in i order to maintain the correct mixture,

diagrammatically one form of device for ac! complishment of thedesirable results aforementioned, and the device will nowbe de scr bed, it being understood that various changesmay be made in the details thereof without departing from my'invention as de fined 1n the appended claims;

ln the drawing the numeral 5 designates a pipe adapted to conduct to the desired point or points of use amixture of the gases su pliedthrough the respective pipes 6 and said gases-being of dilferent quality or combustion calorific value. Pipes-6 and 7 are adapted to discharge through orifices 8 and 9, respectively, into a suitable chamber 10 leading to pipe 5, said orifices being proportioned with respect to each other in accordance with the approximate heating value of the respective gases to provide a mixture of VVith-the foregoing arrangement, obviously the outlet pressures at the two orifices 8 and 9 will always be equal. Thus, if the demand for the mixture of gases flowing through pipe 5 remained constant and if the heating values of the respective gases flowing through pipes '6 and 7 remained constant a substantially constant heating value of the mixture could bemaintained by the means just described However, in practice either or both of the gases in the respectivepipes G and 7 may be sub ject torathcr wide variations in heating value, thereby tending to vary the heating value of Such changes or variations in heating value of the respective gases ordinarily talieplaee rather slowly or gradually, and the means new to be described are adapted to compensate for such variations whereby the heating value of the 'mixture is maintained substantially constant.

Said means may comprise elements constructed and adapted to function substantially in the manner disclosed in the aforementioned Kruse application. Thus, I preferably employ a. suitable form of valve 11 adapted to control the rate of flow of gas through pipe 7. It will be understood, how

, ever, thatisaid Valve c 01 such a valve might'i es sentialsof standardtypta of calorimeter hence warrant also be provided for controlling the-rate" oiEi ltd flow" of- 'gassthrough pipe 6.'f;1.'Val'vej 11 is. ion herein: 1 adapted to, be automatically operated t0. reg-i p,

ulate the rate ofjsupply of ne otf'the gases *suitabl'ejl'eve'r mechanism 32, with a piston 33 relative to; the other Whcreby the -mixture'-op erating within a cylinder 34, the opposite flowing throughpipe ai is maintained or con .ends'of said pyli'nder being connected by no-more extended descripstarit heating value'pen'unit volume, Ac- E'l'meansofpipeS and'36' with longitudinally cordingly pipe 5 Jis tapped to" permit withspaced points of ajsl-ide valve cylinder 37. A

-drawal-of a continuous sample of the-mixture fluid pressure pipe-38 leads'into cylinder 37 through a suitable.-'condi1it,;12.* i Conduitji12jlintermediate pipes 35 and36, the other end v illustrated the'test gas, combustion "air and 35 and 36- leading leads to'the intake of a suitablig wetidisplacef of pipe 38' being connected to the discharge ment pump 13,,the' latter being'zadap'ted .to sideof a'suitable oil pump 39,also driven by supplythe sample to the burner of acaloriinmotor 17 whereas'the inlet side of said pump eter indicated generally ,at 14, additional: is connected by means of a common pipe '40 -Wet displacement pumps 15 and 16; being andbranch pipes*4-1 and42.with the opposite provided forre'spectively supplying the cal-' ends of cylinder 37. Jointly slidable within .orimeter with combustion air and cooling air. cylinder 37 1s a pair of spaced pistons or Pumps 13, 15 and 16 maybe driven by a comblocks 43 and 44 adapted to selectively conmon motor 17, Whereas by the arrangement trol communication between pipe 38 and pipes ,to the upper and lower cooling air are supplied in predetermined ends of cylinder 34. t, proportions under like conditions of temper- Movement of blocks 43 and, 44 from the ature, pressure and saturation. neutral position illustrated is effected and Resistance thermometers 18-a'nd 19 are arcontrolled by connection of the piston rod 45 ranged in the stream of'cooling air to be at one end to a pair of balanced difl'erential subjected respectively to the temperature of pressure floats 46 and 47 and at the other the latter before and after the heat transfer, end to an ad ustable tension spring 48. The said resistance thermometers, being c0nnectinterior of pressure float 46 communicates ed in a Wheatstone bridge, indicated at 20, With pipe 6 by means of pipe 49, that is, on having associated devlces arranged to be inthe upstream side of orifice 8, whereas the influenced thereby for operating suitable in terlorof pressure float 47 communicateswith strumentalities including amember 21 adaptpipe 7 by means of pipe 50, on the upstream ed to be moved in a direct-ionj'a nd to a dgree. side of orifice 9. Thus assuming a proper corresponding with the character and value adjustment of the tension of spring 48, with of any variations in total heating value of a consequent adjustment of the degree of th t t opening of valve 11 to provide a gas mix- The instrumentalities directly controllable ture in pipe 5 of predetemined total heatin by the Wheatstone' bridge may preferably Value, the pressure drop across orifices 8 ant include a galvanometer needle 22 having 9w1ll be proportional, thereby permitting the associated therewith a switch 23 havingan blocks 43 and 44 to remain in the neutral posioperating solenoid 24 which serves in contion illustrated.

junction with a contact drum 25 driven by However, upon a predetermined variation motor 17 to control the operating electromag- (either an increase or a decrease) in the total nets 26 and 27 of a ratcheting mechanism 28. heating value of the combustible mixture Said ratcheting mechanism in turn is utilized passing through pipe 5, as measured by the to move the member 21 for varying the recalorimeter in the manner aforedescribed, a sistance of an adjusting rheostat 29 connected bridging contactor 51 carried by the member in the WVheatstone bridge to restore the bal- 21 is brought into engagement with one or ance crane latter foil'o'wing urrbalaneing-the other of two pairs of contacts 52 and 53. thereof due to variation in the total heating Said pairs of contacts are adapted to respecvalue of the fluid in conduit 5. A recorder 'tively control the energizing circuit of revers- 30 may also be connected with the driven ing switches 54 and 55, whereby an electric member of said ratcheting mechanism, if motor 55 or the like may be connected to lines desired. L L for operation thereof in one direction In practice the motor 17 together with the 01' the other to increase or decrease the ten- Wheatstone bridge and the various operatsion of spring 48. Said tension varying ing coils may all be supplied from a common means may comprise a worm 57, having suitsource of direct current, although in the con able connection with the motor and meshing struction illustrated the VVheatstone bridge is with a gear 58 supported in bearing bracket indicated as supplied with direct current 59. Gear 58 is provided with a concentric from a battery 31, the other instrumentalities threaded o ening adapted to receive a threadbeing supplied from a separate source of cured rod 60 or effecting upward or downward rent indicated at lines L ,L I movement of the, latter in accordance with The aforedescribed elements comprise the the direction of rotation of said gear. Spring As'shown, valve11is connected through i 4:8 is connected to the lower end of rod 60, whereby the controlling effect of pressure floats 46 and 47 upon the position of blocks 43 and id is modified.

Thus it the total heating valueof the mixture passing through pipe 5 decreases from the predetermined value due to a decrease in the total heating value of the gas supplied from. pipe 6, the effect of such decrease is relayed by means ofthe calorimeter and its associated elements to cause bridging con tactor 51 to engage contacts 53, thereby completing the energizing circuit of switch 55 to effectoperation of motor 56 in a direction to cause lowering ofi'od 60 to decrease'the tension' of spring d8. Blocks 43 and 44s are thus lowered to effect communication between pipe 42 leading to the intake side oi pump 39 and pipe 35 leading from the cylinder 34 above piston 33 and to also effect communication between pipe 38 leading from the discharge side of pump 39 and pipe 36 leading to'the cylin der below piston 33. Piston 33 willthereupon be moved upwardly to eiiect closing movement oi valve 11, the degree of closure ofvalve 11 being proportional to'the decrease in total heating value of the mixed gases, whereby the quantity otgas supplied through pipe *1" isproportioned with a'espect to the quantity passing through pipe 6 to provide a minture'oi the desired total heating value;

In the above manner the device is adapted to compensate forgradual changes'in the total heating value of the combustible. mixture due to chahges in the total heating value of one or more of the constituent gases. Ubviously, however, if there is a rapid or sudden increase or decrease in thedemand for the combiistible mixture, such change would tend to vary the predetermined proportionality oi the rates of flow of the gases through orihose 8 and 9. For example, it the demand for the combustible mixture were doubled, it is obvious that the rate of flow through orifice '9 would not be increased in proportion to the increased flow through orifice 8 due to the partially closed positioning on 1 valve 11. However, valve 11 is additionally subjected to control by the pressure floats 46 and lhavhich tend to maintain the pressure drop across orifice 9 proportional to the pressure drop across. orifice 8; subject, however,

.to the existing tensionupon spring 48 as et- ;tected by the determinations of the calorimeter, so that variations in the demand for the combustible mixture are substantially instantaneoiisly compensated for. In this way the desired proportionality oi the gas flows s insured under all conditions, whereas the gradual changes'in the total heating value oi the mixture are compensated for by the calorimeter andits associated manner aforedescriloed. I

elements in the l have thusprovided a quick acting device for maintaining a constant quality or total heating value of a combustible mixture, whereby the lnherent d sadvantages of a de- "vice dependent solely upon the determinafluids 'in accordance with the differential value of pressure conditions at the inlet sides 0i the respective orifices to thereby compensate for rapid variations in the relative rates of flow of the fluids, burning a sample flow of the mixture to ascertain the total heating value per unit volume of the latter, and additionally varying the rate of supply of said.- one oi said fluids in accordance with the as certained value to thereby maintain the total heating value per. unit volume of the mixture substantially constant.

' 2. A device for controllingthe total heatlng value per unit volume of a flow of com bustible fluid, comprising means for supplymg from separatesourccs the constituents of said flow, a mixing chamber having proportioned fixed orifices through which said constituents .areadapted to flow to normally provide a mixture of predetermined total heating value, means for automatically varying the rate of flow of one of said constituents in accordance with variations in the rate of flow ofanother of the same to thereby maintain said total heating value of the mixture, said means comprising diiierentially related pressure responsive devices respectively su jected to pressure conditions on the upstream sides of" said orifices, and avalve controlled by the diderentialaction of said till devices, said valve being adapted to regulate subjecting the rate oil said constituent combustible flow tocontrol in accordance with variations in the rate. of flow ofanother com bustible fluid.

4. h Apparatus for controllingthe flow of a combustible fluid constituent of a composite flow of combustible fluid, comprising a com bustion calorimeter for determining the total heating per unit volume of said stituent combustible flow to control in accordance with Variations in the rate of'another constituent combustible flow, said means comprising a chamber having fixed orifices adapted to provide a predetermined proportionality of said constituent flows under conditions of predetermined pressures on the upstream sides of said orifices, a valve for regulating the pressure on the upstream side of one orifice, differentially connected pressure floats for effecting operation of said Valve, and means for respectively subjecting said floats to pressure conditions on the upstream sides of said orifices.

5. In a device for controlling the relative rates of flow of combustible fluids of unlike quality to provide a flowing mixture thereof of predetermined total heating value per unit volume, the combination with a conduit for each of said combustible fluids, each of said last mentioned conduits having a fixed orifice through which the respective fluids are adapted to flow, a conduit for the mixture of saidfluids, a calorimeter adapted to burn a continuous sample of said mixture of fluids, means for varying the rate of flow of one of said combustible fluids in accordance with the determinations of said calorimeter, and means for also varying the rate of flow oil said combustible fluid in accordance with varia tions in relative values of the pressure drops across said orifices. 6. The method of maintaining substantially a given total heating value per unit volume of a composite flow of combustible gaseous fluid; which comprises burning a sample flow of the fluid of said composite flow in a manner to determine the total heating value per unit volume of the latter, regulating the rate of flow of one of the combustible constituents of. said composite flow in accordance with the valueso detern'iined, and modifiying the regulation so eflected to compensate for variations in the relative rate of flow of another: ot the combustible (.ODSllllllOlli'S of said composite flow.

In witness whereof, I have hereunto subscribed my name.

CLARENCE S. PINKERT ON. 

